Revert questionable fix

primitives/state-machine/src/ext.rs

@@ -464,9 +464,8 @@ where
 		}
 
 		self.mark_dirty();
-		let overlay_count = self.overlay.clear_prefix(prefix);
-		let (all, count) = self.limit_remove_from_backend(None, Some(prefix), limit);
-		(all, count + overlay_count)
+		self.overlay.clear_prefix(prefix);
+		self.limit_remove_from_backend(None, Some(prefix), limit)
 	}
 
 	fn clear_child_prefix(

primitives/state-machine/src/overlayed_changes/changeset.rs

@@ -410,15 +410,10 @@ impl OverlayedChangeSet {
 		&mut self,
 		predicate: impl Fn(&[u8], &OverlayedValue) -> bool,
 		at_extrinsic: Option<u32>,
-	) -> u32 {
-		let mut count = 0;
+	) {
 		for (key, val) in self.changes.iter_mut().filter(|(k, v)| predicate(k, v)) {
-			if val.value_ref().is_some() {
-				count += 1;
-			}
 			val.set(None, insert_dirty(&mut self.dirty_keys, key.clone()), at_extrinsic);
 		}
-		count
 	}
 
 	/// Get the iterator over all changes that follow the supplied `key`.

primitives/state-machine/src/overlayed_changes/mod.rs

@@ -315,8 +315,8 @@ impl OverlayedChanges {
 	/// Removes all key-value pairs which keys share the given prefix.
 	///
 	/// Can be rolled back or committed when called inside a transaction.
-	pub(crate) fn clear_prefix(&mut self, prefix: &[u8]) -> u32 {
-		self.top.clear_where(|key, _| key.starts_with(prefix), self.extrinsic_index())
+	pub(crate) fn clear_prefix(&mut self, prefix: &[u8]) {
+		self.top.clear_where(|key, _| key.starts_with(prefix), self.extrinsic_index());
 	}
 
 	/// Removes all key-value pairs which keys share the given prefix.